[#nlohmann-basic_json-00-is_null] = xref:nlohmann.adoc[nlohmann]::xref:nlohmann/basic_json-00.adoc[basic_json]::is_null :relfileprefix: ../../ :mrdocs: return whether value is null == Synopsis Declared in `<nlohmann/json.hpp>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- constexpr bool is_null() const noexcept; ---- [.small]#Created with https://www.mrdocs.com[MrDocs]#